Process for producing polyurethane

• US 5,100,926 A
• Filed: 07/17/1989
• Issued: 03/31/1992
• Est. Priority Date: 07/18/1988
• Status: Expired due to Fees

• Current Assignee: Sanyo Chemical Industries Limited, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Sanyo Chemical Industries Limited, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Nagata, Kouzaburo, Kondo, Kanemitu, Isaka, Takuji, Nomura, Takao, Ishikawa, Isao, Ukai, Junzo
• Primary Examiner(s): Kight, III, John
• Assistant Examiner(s): Truong, Duc
• Application Number:
  US07/380,798
• Time in Patent Office: 988 Days
• Field of Search: 521/163, 521/55, 521/58, 521/160, 521/161, 521/137, 521/914, 528/76, 528/54, 528/44, 528/53, 528/59, 528/61, 528/73, 528/75, 528/55, 528/914, 264/51, 264/328.1, 264/328.6, 264/328.8, 524/186
• US Class Current: 521/163
• CPC Class Codes: C08G 18/6529 Compounds of group C08G18/3225 or polyamines of C08G18/38
• CPC Class Codes: C08G 18/6685 with compounds of group C08G18/3225 or polyamines of C08G18/38
• CPC Class Codes: C08G 2110/0041 having specified density
• CPC Class Codes: C08G 2120/00 Compositions for reaction injection moulding processes
• CPC Class Codes: Y10S 521/914 Polyurethane cellular product formed from a polyol which has been derived from at least two 1,2 epoxides as reactants

Abstract

Disclosed herein is a process for producing polyurethane moldings having good physical properties and good receptivity of electrostatic coating, said process comprising reacting a polyoxyethylene chain-containing polyether polyol having 2-4 hydroxyl groups and a hydroxyl equivalent higher than 750 as the high-molecular weight polyol, diaminotoluene and a low-molecular weight polyol having a hydroxyl equivalent of 30-100 as the low-molecular weight, active hydrogen-containing compound, with organic polyisocyanates in specific equivalent ratios respectively. The process may advantageously applied to injection reaction molding.

Claims

1. A process for producing polyurethane by reacting an organic polyisocyanate, high-molecular weight polyol, and low-molecular weight, active hydrogen-containing compound with one another in the presence of catalysts and, if necessary, blowing agents/ foam stabilizers, and other adjuvants, said process comprising using a terminal 7-30 weight % of polyoxyethylene chain-containing polyether polyol having 2-4 hydroxyl groups and a hydroxyl equivalent higher than 750 [component (a)] as the high-molecular weight polyol, diaminotoluene [component (b)] and a low-molecular weight polyol having a hydroxyl equivalent of 30-100 [component (c),] as the low-molecular weight, active hydrogen-containing compound-, with the equivalent ratio of component (c) to component (a) being 8-12 and the equivalent ratio of component (b) to component (a) being 0.15-1.0.

2. A process set forth in claim 1, wherein the equivalent ratio of the low-molecular weight, active hydrogen-containing compound to the high-molecular weight polyol is 8 to 13, preferably 9 to 12.

3. A process set forth in claim 1 or 2, wherein the NCO equivalent of the organic polyisocyanate is 130 to 200.

4. A process set forth in claim 1, wherein the hydroxyl equivalent of the polyether polyol [component (a)] is 1,500 to 3,000.

5. A process set forth in claim 1, wherein the hydroxyl equivalent of the low-molecular weight polyol [component (c)] is 30 to 50.

6. A process set forth in claim 1, wherein the equivalent ratio of the diaminotoluene [component (b)] to the polyether polyol [component (a)] is 0.2 to 0.8, preferably 0.25 to 0.7.

7. A process set forth in claim 1 or 4, wherein the content of polyoxyethylene chains in the polyether polyol [component (a)] is 5% and above, preferably 7 to 50%, and more preferably 10-40%.

8. A process set forth in any of claims 1 to 7, wherein the blowing agent is water, a volatile blowing agent, and/or a gas admitted by force and the resulting polyurethane has a density of 0.3 g/cm³ and above.

9. A process set forth in any of claims 1 to 8, wherein polyurethane moldings are formed by reaction injection molding process.

10. Polyurethane produced by the process set forth in any of claims 1 to 9.